Air brake



Jan v17 .Filed NOV. 25' 1944 BRAKE CYL.

I nventor Lynn Picker-r1( attorllegs branch which leads through a Patented Jan. 1, 1946 UNITED STATES r .1 :rr.1\1'r oFFl-ca Lynn I. Pickert, The New York tion "of New Jersey Watertown, N. Y., assignerk to Air Brake Company, a eorporat Application November z5, 1944, serial No. 565,087 l claims. (c1. eos-es) This invention relates to yrelease valves, primarily intended for use in releasing the brakes on cars preparatory to setting them out of a train for switching operations. f

. The device can also be used to release stuck brakes.

'I'he invention is in the nature of an improvement on the structure described and claimed in Patent 2,302,377, issued November 17, 1942, and assigned by the present applicantl to The New York Air Brake Company.

In the device of the prior patent use is made oi' a. slide valve to interrupt the connection between the brake controlling valve device (hereinafter called the control valve) and the brake cylinder and then vent the brake cylinder. This device operated with entire satisfaction but required a relatively large slide valve in order to afford ports of sufficient ow capacity.` This made the devicel unduly large and heavy. Furthermore the use of `a. slide valve entails considerable expense in manufacture.

The purpose of the present invention isto retain the operating .characteristics of the original device, secure a large flow capacity by the use of poppet valves, arrive at a simple and inexpensive construction and still so arrange the parts that neither the failure of the diaphragm nor the failure ofthe loading spring can result in therloss of braking air. n

The invention willnow be described with reference to the accompanying drawing in which the single figure is an axial vertical section of the release valve in its normal position, the valve being shown connected to an AB control `valve and to a brake cylinder, each drawn in miniature to save space, while indicating essential connections.

The pipe bracket of an AB control valve is indicated at 6, the body of the emergency portion is indicated at 1, and the body of the service portion at 8. 'I'he usual reservoir bleed valve is indicated at 9. This bleed valve need not be dispensed with, but it would be supplantedV for most purposes by the release valve of the present invention;

The brake pipe is indicated at Il and has a y dust collector I2 to the pipe bracket. The brake cylinder connection appears at I3, the auxiliary reservoir connection at I4, and the supplemental reservoir connection at I5. Fragments of the two reservoirs appear in the drawing and are identifiedby legends.

A portion oi.' the brake cylinder is indicated by the numeral I 6. l

All the parts so far described are of known construction, the AB control valve being standard on American railroads.

I with an annular passage YThe release valve forming the subject of the present invention is interposed between the brake cylinder connection I3 and the brake cylinder I6.

The main body ofthe valve is indicated at 2Iv and is in the'form of a casting, having a chamber 22 with which the-pipe I3 communicates and a chamber 23 in free communication by a pipe 24 with the brake cylinder I6.

The body 2l is mounted on a pipe bracket 25 conventionally indicated in the drawing, the pipes I3 and 24 being connected to the bracket. The bracket could assume various forms and no at'- tempt to illustrate it in detail has been made.

v The chambers 22 and 23 are separated by a downwardly presented valve seat 26. This seat isshown as formed on an insert is sealed by gaskets 28 and 29 and which Vis clamped by a cap 3| ofhthe form clearly shown in the drawing.

The' cap '3i is bolted to the top of the housing 2l and clamps the peripheral margin of a exible diaphragm 32 shown as'of the slack or corrugated type.

The lower vside`oi the diaphragm is subject to the pressure in the chamber 22. The diaphragm is subject on its upper side to pressure in a chambei- 33 .which is connected by a passage 34 with a chamber 35 formed in the lower end oi the housing 2l. The chamber 23 and the chamber 35 communicate with each other through the bore of la bushing 36 which is pressed into an opening extending between these two chambers. The bushing 36 has lateral ports 31 which communicate 38 and through .the passage 3i! with passage 24 and consequently with the chambers 33 and 35.

Controlling dischargefrom the bottom f the chamber 35 is an upwardly presented valve seat 39 formed on the upper end of a bushing which is pressed to place A valve body 4I carries on yits lower end a rubber faced valve 42 which normally seals against seat 39 and carries at its upper end a rubber faced valve 43 which may close against the seat .26- at which time the valve 42 will be liftedfrom its seat 39.

The'valve42 is'shown'in the drawing as a separate component connected to .the valve body 4I by a machine screw.. The valve 43 is formed integrally withzthe body.` An upwardly extending stem 44 passes through the center of the diaphragm 32 and diaphragm by a flanged sleeve 45, a thrust plate 46, which overliesthe diaphragm, and a nut 41. The extreme upper end of the stem 44 projects abovethenut 4'Iand is reduced in diameter as iri-l or spider 21 which is clamped to the center of the' l neared at 4 8. This reduced Vena 481s guided a bushing 49 pressed into the cap 3|. A biasing Y offspring 51 i so: as Ltrropenfthe?.

diaphragm.' 32.? Consequently theeadmissinneof: t pressure; toffthe fpipe l.3fwill.zdevelcp-' lttleeiteany. upward;actineff'pressurm dilerential-z` onfxthefdia-e `tilted soifthatthieivalve-zbodys'llikzisrorcedupwardp.

'pressureleaseepositomand'.ventsthe piper! 3,1;theezconsefff 7:5;-

spring` 5| of moderate strength urges the diaphragm 32, the stem ,44 and the valve body 4| downward so that the valve 42 is normally seated 5 and the valve 43 is normally unseated. The valve body 4| has a peripheral flange or rim 52 which encircles it y .betweem theV valvesf42 i and 43, lthe, flange being-eso: located thatl whensvaive; 42'?. isf-1 closed, the flange 52 fully exposes the ports 31. 10 However if the body 4| is moved upward suiiif-f` ciently to close the valve 43 against the seat 26` the ports 3'! are throttled but not completelitr the bushing 36 by radial Wings 53.'l

A housing 54 of the form shown is attached a spider 59 clamped betmaenntlielousingsfZl'y and' reducingzpressure ain-ath efbrakeepipeelj u control valve will function in the normal to:admittairlinder;pressureutitheepipe|3E This seat'26 finisce chamber: 23:5arrdt1byr` lppecZil t'oethef: f off theT brakes-1 At theesanre timeairrwiilflomzfreelyf tliroughfithe ports 31torethespaceii33 .above'ffthef the elect will be to isolatexchambers122:and .123: from oneanother,l throttle-butrroticloseitheffports overcome the stress of the.spring;5|;iandatl:lle651 pressure acting? on: the;l srnail;areas.V ot: valve* 3 whicl'ris' exposedzawitliinseatfz.: 'Ihefpartse-areedesignedsto. meet mist-requirement;

The electI-isito: disconnectathe; chambersfv.- 223;

angeezzrto: chamber'sand thence to'. atmos-jf plier-e; Consequentlyftli'e :brake:ecylinder, willirej-aVA main vented: as longf: asf.I pipe: ,'32 remains funden Ifttlle AB control `valveifmoves-,-,to;re

quent venting of chamber 22 will permit the spring 5| to restore the release valve to the position shown Vin the drawing.

If Va car is to be cut out of a train which is stopped with the brakesapplied, the pull rod attached to the member 51 is operated in vany direction forcing the Valve body 4| up, closing the Sbrake. connection Scand-venting brake cylinders` Thefexistingacharges. in ltlieireservoirs would be retained and only the air in the brakeV cylinder will be vented. After this operation, the brake pipe is disconnected and the car can vbep cut out of the train and switched at will. When thercar is again connected in a. train and theybrakezpipetisscharged, the resulting shift of theeA'BcontroLivaiize to release position will vent pipe I3 and, consequently restore the release vaiveeto normal'iconidition. Y

In-rcaseeof a stuck AB control valve, operation ofthe release valve tas above described willvent thebrakeylindrfandfnaintain '-th'efb'rake equipment i on.di thati'- carg inoperativ'eunti-l l the# con'tlrolv vaiveemovesrbaolrltrelaseipositionf *Ii'flth'ercona trol valve does move to relasesipositintliere leaseflvalve-f resets and 'restores the brake: equipment on the car to normal operating condition'.`l A'Vlh-"il tl'iei invention h'as lfbeenfldescribfed-iand discussedf'fa'sSused'iwith"a"controlrvaivefof'the"TABL type, itfisf availableforuse-betweerr'-anycontrol" valve -and its"brak'e1 cylinder?.v Itisf-.peculi'rlyg valuable with the AB controlvalve'becausathat valve is: used'i fr"freight service* and:J requires largewreservoirf' volumes." Furthermore.. freight trains*areverylonggso'thatthetimerequiredfitf charging .reservoirs :entails seriousdelaysin train asinglefreservoircontrollvalve: suchr example;I

as: vthe wellfknownK type triplet'. value1.. It'an;

bemsedfaiso' with'nontrol valves; on'. passenger..

cars. Y D f Y 'wnatiscraimedim 1. A .release valueL forfinterposition betweern a v contro1`valveiandalbrale:cylindennorrnally:cone` tirolled" therebyti comprising. inl comlinationa double' beat .'poppetyalve.havingfalnormalposion in which itv connectsth`ecconto1ivalveoandrlthe tir-alie cylndriand 'anahnor-malpositonmyvhch. it disconnectsthem andvents the-Brake cyliildr;. means exerting on the valve a moderatelbiasto:

' ward` normal position; ,a.,doublei actingpressure motoncliargedLbyL the -control 'lvalve dringi brake applications, connected.A to said: pnppet lvalve, .and controlled. .ati' least lin para by throttlig, means so relatedto` the puppet i,valve Jthat," pressures ir-1^ the .motorare balancedrenderingitlie :motor inert Whenthe `puppet vali/ei is .in normal..positionr but are'. unbalanced.y when .,thepoppet u Valve .'isMmoved away fromnormaLposton vsuch unbalan ce ecref. atingU a dominant.' bias@.towardlabnormall posi-- f tirrr., andlmeans, operable. .toy freeM the.,v puppet.

valve away. fliomsaid .normallposition suciently tordevelopi.said.dminant,bias; f j

2. The' combination deflediinclaimll liniwhich; the. *doubl acting moto-ri. i corm ris'es... .a. movable abutmentalwayssub'j ect l unione side to braking.

pressureedvelopedgby., the controllvale and. on.

tne-otlier-v,sidatopressurerma chamber .wliiel-Lis.: freely, vented. by, the poppet valev when in lits. abnormalcposition, .and the .Itlf'i'rottlingimeans restricts :.a.passage ,alwaysi atlleast. partially openK between-the:brake-cylinderandssaid'chamber. l

3. A release valve comprising in combinatona valve; housing-havingsmcontrol.valize connection,

a-lbnaleecylinderi connectionTnv aavalve; seattcorn-1 trollingr a free communieationbetweenasaidmom nections and an opposed valve seat controlling `a vent from the bra-ke cylinder connection; a double beat poppet valve adapted to close against said seats selectively, said valve having a normal position in which it closes ag inst the second named valve seat and a releasing position in which it closes against the first named valve seat; yielding means biasing said valve toward normal position; a movable abutment connected to said valve and always subject to pressure in the control valve connection in a direction to urge the valve toward releasing position; means forming a chamber on the opposite side of said abutment and in free communication with the vent valve seat; means associated with the do-uble beat valve and serving to place said chamber in free communication with the brake cylinder connection when the valve is in normal position, and to restrict said communication at other times; and means for forcing said valve toward said releasing position.

4. A release valve mechanism for interposition between a control valve and a brake cylinder whose pressure is normally controlled thereby, said mechanism comprising an expansible 'chamber motor having two working spaces separated by a movable abutment, the first working space being subject to braking pressures developed by the control valve; a double beat poppet valveY connected with said abutment to be shifted between two functional positions by the reverse.

4movement of the abutment, said valve including means effective in one of'said functional positions to restrict a normally open communication between the brake cylinder and the second working space, the two functional positions of the valve being a normal position assumed when the abutment is shifted toward the first Working space in which the brake cylinder, control valve and second working space are in free communication with one another, and a releasing position in which the brake cylinder and control valve are disconnected from one another, the brake cylinder is in restricted communication with the second working space and the latter is freely vented to atmosphere; yielding means insuillcient to resist effective braking pressure in the first working space and biasing the abutment toward that space to establish the normal position of the valve; and manually operable means for effecting a shift of said valve toward releasing position.

5. A release valve comprising in combination a valve housing having a control valve connection, a brake cylinder connection, a valve seat controlling a free communication between said connections, an opposed valve seat controlling an atmospheric vent, and a flow regulator ported to permit ow between the brake cylinder connection and the vent valve seat; a double beat poppet valve adapted to close against said valve seats selectively and having means serving in one position of the valve to throttle but not close the ports in said flow regulator, said valve having a normal position in which it closes against the secondnamed valve seat and exposes the ports in said flow regulator and a releasing position in which it closes against the first-named valve seat and throttles the ports in said ow regulator; yielding means biasing said valve toward normal position; a movable abutment connected to said valve and subject to pressure in the control valve connection in a direction to urge the valve toward releasing position; means forming a chamber on the opposite side of said abutment and in free communication with the flow regulator ports and vent valve seat; and manually operable means for forcing said valve toward releasing position.

` LYNN I. PICKERT. 

